Low Compression in 1 and 6

[Obsessionw/Boost]

What would cause low compression in cylinders 1 and 6.
A friend of mine is having trouble with his account on here, so I'll ask the question for him.
He did a cold compression test and here are the results:

Cylinders:
1- 110
2- 155
3- 155
4- 155
5- 155
6- 110

What would cause this to happen?
Thanks, Ryan

 

[rawmk3]

Well being that those two are commonly the ones that wear the most, I would do a leak down test and find out if you are looking at rings or not. Also look down into the cylinder bores and see if there is any oil or coolant in there. There are tons of things that could cause that, but eliminating simple things first would be the best before asking such a question with a wide range of possibilites. Could be rings, bearings, valves, HG, i mean there are tons of things. So I would check into things a lil closer first. Do a leak down, and see if its valves, or rings. If there are any fluids its a HG. If the leak down doesnt hold pressure, then valves, and if it slowly leaks out then rings.